Many devices and systems are provided to control heat build-up in a vehicle. For example, conventionally a cooling fan powered by the vehicle electrical system is provided to provide airflow over and through various components of the vehicle cooling module(s) such as the radiator, oil cooler, transmission fluid coolers, and other heat exchangers which may be disposed in the engine compartment or associated with the drivetrain. Likewise, it is known to provide active grille shutter (AGS) systems which typically comprise a plurality of louvers or shutters which can be pivoted to a variety of angles between a fully opened configuration and a fully shut configuration. Indeed, it is known to provide AGS systems comprising upper and lower louver or shutter assemblies, allowing control of the amount of exterior air entering the engine compartment and/or passing over elements of the vehicle drivetrain. AGS systems are often used as supplemental cooling systems to increase/decrease exterior airflow into the engine compartment and/or over components of the drivetrain, particularly when a vehicle is in motion.
Each of these systems consumes power, albeit in different ways. The cooling fan requires power derived from a vehicle system to operate, and power usage is controlled simply by controlling a fan speed. The airflow provided by the AGS system is controlled by adjusting the shutters to a desired position or opening level between a fully closed (least airflow and least aerodynamic drag) configuration to a fully open (most airflow and most aerodynamic drag) configuration. Vehicle power consumption relating to AGS system operation is primarily a function of the aerodynamic drag created by the selected AGS system position.
A required level of airflow into/through the vehicle engine compartment and/or over components of the drivetrain may be achieved by a combination of cooling fan speed settings and AGS position. For example, a same level of airflow may be achievable by a higher cooling fan speed setting and a more closed AGS setting, or alternatively by a lower cooling fan speed setting and a more open AGS setting. However, each combination of AGS position/setting and cooling fan speed results in very different vehicle total power consumption levels due to cooling fan power consumption and aerodynamic drag differences associated with individual pairings. A particular combination of AGS setting and cooling fan speed may provide a desired or required level of cooling airflow over one or more vehicle heat exchangers, but may be undesirable in terms of vehicle power consumption and efficiency. Accordingly, a need is identified for methods and systems for minimizing the power consumption required to provide a desired airflow to/over/through one or more vehicle heat exchangers and other components of the vehicle cooling module in vehicles using a combination of a cooling fan and an AGS system.
To solve this and other problems, the present disclosure relates to methods for controlling power consumption in vehicles wherein cooling airflow to various vehicle heat exchangers is provided by a combination of a cooling fan and an AGS system, and to systems for implementing the methods.